Vacuum cleaner

ABSTRACT

A vacuum cleaner having a hollow housing in which air flows from the suction inlet adjacent to a brush-type agitator that contacts the surface to be cleaned to an outlet in the housing. The air path passes through a dust collecting bag and thereafter cools a motor-fan unit and finally exits through the outlet in the housing. The structure includes a biasing assembly for the agitator which is yieldable; and is further provided with an adjustment that selectively changes the vertical distance between the brush and the surface to be cleaned. The structural arrangement further comprises a parking device which lifts the rotary agitator from contact with the floor when the vacuum cleaner is not being used, and an adjustment means for resetting the position of the rotary agitator when the brushes are worn.

United States Patent Erikson et al.

[45] Dec. 24, 1974 Milos Vukotic, Skarholmen, both of Primary ExaminerEdward L. Roberts Attorney, Agent, or Firm-Alfred E. Miller Sweden [73] Assignee: Aktiebolaget Electrolux, Stockholm, [57] AFSTRACT Sweden A vacuum cleaner havmg a hollow housing in whlch air flows from the suction inlet adjacent to a brush- [22] Fled: Sept- 1972 type agitator that contacts the surface to be cleaned to 2 Appl 292 172 an outlet in the housing. The air path passes through a dust collecting bag and thereafter cools a motor-fan unit and finally exits through the outlet in the housing. [52] US. Cl. 15/372, 15/392 The Structure includes a biasing assembly for the [51] it. Cl A471 5/34 tator i h is yieldable; and is further provided i [58] held of Search 15/368 an adjustment that selectively changes the vertical dis- 15/372 361 tance between the brush and the surface to be cleaned. The structural arrangement further comprises [56] References C'ted a parking device which lifts the rotary agitator from UNITED STATES PATENTS contact with the floor when the vacuum cleaner is not 478,942 7/1892 Pease 15/368 X being used, and an adjustment means for resetting the 1,143,959 6/1915 Harris 15/373 X position of the rotary agitator when the brushes are 2,416,420 2/1947 Taylor l5/372 worn, 2,627,623 2/1953 Humphrey .1 15/373 x 3,012,267 12/1961 Kemnitz 15/372 8 Clalm'S, 6 Drawing Figures F lllu. 34 l.

36 looooooooool l [11 l j l' l l I2 1 l l 84a 60a 78 g 94 74 5/68 Z 52 \U l 66 l 5 86 i 1 8 48 32 26 l 53 '50 l 60 74 5 1 i 50 "i: I. "11110 A? llllh l 1 1 PATEHTED DEC 2 4 I974 saw u 5 OOOOOOOOO VACUUM CLEANER BACKGROUND OF THE INVENTION Vacuum cleaners are known which provide for an adjustment of the rotary rug agitator in a vertical plane depending upon the height of the pile or nap in the rug or carpet to be cleaned. These known structures provide for the vertical adjustment of the rotary agitator in which the whole nozzle body is selectively lowered or elevated, often with the aid of the front or rear wheels, and in which the optimum distance between the nozzle and the working surface is altered. This arrangement frequently causes unsatisfactory working results.

SUMMARY OF THE INVENTION This invention relates to a vacuum cleaner structure provided with an adjustable, yieldable biasing assembly for a rotary brush-type agitator driven by an electric motor whereby the vertical distance between the agitator and the floor can be changed as desired. Moreover, the vertical distance of the suction inlet from the working surface remains the same regardless of the change in the vertical distance between the brush-type agitator and the surface to be cleaned.

It is an object of the present invention to provide a vacuum cleaner structure having a yieldable biasing assembly for a rotary brush-type agitator that can be easily and rapidly selectively elevated or lowered for cleaning different pile heights of rugs or carpets. The brush-type agitator, because of its yieldable mounting, easily passes over floor mounted objects, such as door saddles.

A further object of the present invention is to provide a parking device for a vacuum cleaner which lifts the brush-type agitator to an elevated position out of engagement with the rug or floor surface, and thus avoids deformation of the brush bristles.

Another object of the present invention is the provision of an adjustment means for resetting the brushtype agitator to a position for optimum performance after the brush bristles have been worn down due to continued use of the vacuum cleaner.

An object of the present invention is to provide a knob adjusting means which is provided with an eccentric structure that engages an upstanding projection on a slidable shaft whereby the shaft is moved linearly either forwards or backwards. The brush-type agitator is operatively connected to the slidable shaft and pivoted in a manner to either elevate or lower the agitator.

The invention will now be more fully described with reference to the accompanying drawings wherein:

FIG. 1 is a rear perspective view of a vacuum cleaner embodying our invention.

FIG. 2 is a perspective view of the undersurface of the vacuum cleaner shown in FIG. 1 and embodying our invention.

FIG. 3 is a bottom plan view of the vacuum cleaner constructed in accordance with the teachings of the present invention.

FIG. 4 is a part sectional and part elevational view of the vacuum cleaner taken along the lines 44 of FIG. 3.

FIG. 5 is a sectional view of a detail of construction of the present invention taken along the lines 55 of FIG. 3, and

FIG. 6 is a view similar to the view shown in FIG. 4 with the rotary agitator in its lowered position.

DESCRIPTION OF THE PREFERRED EMBODIMENT The vacuum cleaner, as seen in FIG. 1, is referred to generally by the numeral 10, and comprises an upper housing 12 and a lower hollow base nozzle unit 14. As seen in FIG. 2, the nozzle unit 14 is rotatably supported by a pair of front wheels 16 and rear wheels 18. The upper housing 10 contains a dust bag 20 in its upper portion and motor-fan unit 22 in its lower portion. A suction inlet 24 is shown in FIG. 1 located in the side wall of the nozzle unit 14 adjacent to one end of an elongated rotary brush-type agitator 26. It will be noted from FIG. 6 that the agitator 26 normally projects below the plane of the suction inlet 24 for engagement with the rug or any other surface to be cleaned.

As seen in FIGS. 1 and 2, a flexible conduit 28 has its lower end connected by means of connecting plate 30 to a dirt and dust collecting chamber 32 which partially encloses the rotatable agitator 26.

The upper end of flexible conduit 28 projects out of the upper housing 12 and forms a bend at 30, and is connected to the dust bag 20 in the housing 12. Thus, dirt and dust laden air is drawn up the flexible conduit 28 and into the dust bag 20 where the dirt and dust is collected, and, as seen in FIG. 4, passes through a perforated plate 34 freed of dust particles and thereafter through the motor-fan unit 22 in the direction of the arrows shown in FIG. 4. The air then enters channel 36 adjacent to the rear of upper housing 12 and exits to the atmosphere through a grate 38.

As seen in FIG. 2, the brush agitator 26 is driven by a motor 40 through a toothed belt 42. The brush agitator 26 is supported at its ends by means of links 44, each connected at one end to an end of the brush agitator 26 and at the other end to a shaft 46 mounted for rotational movement in the nozzle unit 14. The shaft 46 is split into two sections and is provided with an offset shaft 48 which is connected to each of the two sections of shaft 46 by means of links 50. The offset portion 48 of the shaft 46 imparts a rotational movement to the latter and this motion in turn provided the means for adjusting the proper distance of the brush agitator 26 to the carpet or other surface to be cleaned.

An elongated rod 52 is illustrated in FIGS. 2, 3, 4, and 6 which is mounted for movement along its longitudinal axis. Both ends of the rod 52 are provided with threaded portions 54 and 56 respectfully. An upper plate 58 and a lower plate 60, having mating portions, are shown assembled and secured together, and forming a connection between the offset portion 48 of the shaft 46 and the end of the rod 52 adjacent to threaded portion 56. In fact, the upstanding parts 58a and 60a of the upper and lower plates 58 and 60 respectively are provided with apertures 62 and 64 through which the threaded portion 56 and the adjacent end of rod 52 passes. The upstanding part 58a is further provided with a nut 59 fixed thereto through which threaded portion 56 of the rod 52 is screw-connected. It will be noted that a positive downward limiting arrangement for the brush agitation of the present device results from the above-described structure.

The elongated rod 52 is axially slidable in sleeve 66 while a brush lift bracket 70 is rotatably mounted in circumferential grooves in the rod 52 having a part 72 that engages the camming surface of the eccentric 74 lo cated on the shaft 76 of rotatable knob 78. As seen in FIG. 3, the knob is provided with a ratchet ring 79 which co-acts with a pawl 81 in the selected position of the knob 78. Surrounding the rod 52 is a compression spring 80 which has one end engaging the sleeve 66 and the other end engaging a surface of the brush lift bracket 70.

The upper housing 12 has an inverted U-shaped handle 82 which in the generally vertical parking position of the vacuum cleaner, as seen in FIG. 4, the rear wall of the upper housing 12 pushes on the end 84a of the parking lifter 84. The latter is pivotable around pivot point A and is provided with a downwardly extending channel 86 having the end of rod 52 provided with the threaded portion 54 passing through an opening 88 therein. The other end of rod 52 imparts motion to the offset shaft 48 which in turn rotates the shaft 46 and thereby lifts the brush agitator 26 to an elevated position and out of engagement with the carpet or floor surface. It should be apparent that the brush agitator 26 is lowered to the carpet or rug engaging position when the handle 82 on the upper housing 12 is swung to a lower position as shown by the arrow B in FIG. 6, and the rod 52 moves due to the action of spring 80 in the direction of the arrows C thereby moving the brush agitator 26 downwardly.

Referring to FlGS. 2 and 5, an operating foot pedal 90 is shown mounted for pivotal movement about pivot point 92 and is utilized to swing the upper housing 12 to a low position where the vacuum cleaner will be able to roll under certain furniture pieces. in this regard, the upper housing 12 pivots about another point 94 and the foot pedal 90 is provided with saw teeth 96 and 98. The foot pedal is further provided with a spring 100 that is connected to shaft 46 and the nozzle unit casing is provided with a stationary stop 102. Thus, when the upper housing 12 is lowered as shown in dotted lines in FIG. 5 and the tooth 96 engages the stationary stop 102, the vacuum cleaning apparatus is in the normal working condition position. However, if it is desired to use the vacuum cleaner under low furniture where there is little clearance, the pedal 90 is further depressed and the upper housing 12 is swung lower to a position substantially horizontal to the floor since the tooth 96 passes under the stationary stop 102 and there is therefore no interference with downward swinging movement of housing 12. The position of the vacuum cleaner shown in full lines in FIG. 5 represents the condition in which the upper housing 12 is substantially vertical and the apparatus is not operative. The spring 100 biases one of the teeth 96 or 98 of the pedal 90 normally in en- I gagement with the stationary stop 102.

the slotted end of threaded portion 54 of rod 52. By

turning the rod 52 in the threaded nuts 53 and 59, the effective length of the rod 52 can be changed. The nut 53 in the channel 86 functions as a lock nut thus locking the rod 52 in its adjusted position relative to the parking lifter 84. It should be noted that this arrangement may be used to calibrate a new machine in order to ensure the proper position of the brush agitator 26 inside the suction inlet 24.

It should be apparent from the foregoing description of our vacuum cleaner structure that by turning the knob 78, the camming surface of eccentric 74 imparts axial movement to the elongated rod 52 which in turn applies a force to the offset shaft 48 of rotatable shaft 46 which consequently results in a change of vertical distance between the brush agitator 26 and the surface to be cleaned in which the resultant change is in the scale 1:1. Thus, the vertical distance of the suction inlet 24 from the working surface is the same regardless of the change in elevation of the brush agitator. This arrangement has the desirable result of ensuring optimum air flow around and through the suction inlet 24 and consequently optimum performance of the vacuum cleaner.

It should be noted that the brush agitator 26 yieldably mounted in our present novel arrangement easily passes over obstructions on the floor, such as door saddles, thus damage to the mechanism is averted.

What is claimed is:

1. A vacuum cleaner comprising:

a. a hollow housing having an air inlet and an air discharge port,

b. a dust collector,

c. conduit means for conducting the air passing through the air inlet and depositing dust into the dust collector and thereafter passing the air out the air discharge port,

(1. an agitator for the surface to be cleaned being located in or adjacent to the air inlet,

f. means for driving the agitator,

f means mounting the agitator for substantially vertical movement including:

1. a rotatable shaft mounted in said housing being operatively connected to the agitator,

2. a resiliently biased member operatively connected to the rotatable shaft for moving the same to yieldably urge the agitator toward or away from the surface to be cleaned,

g. an operator for moving the resiliently biased member, and

h. said resiliently biased member including an elongated rod, a member mounted on said rod having an upstanding projection, said operator being provided with a surface that in one position thereof engages the upstanding projection in order to move the rod in a direction along the longitudinal axis thereof.

2. A vacuum cleaner as claimed in claim 1 further comprising a strap assembly operatively connecting the forward end of the elongated rod to the rotatable shaft.

3. A vacuum cleaner as claimed in claim 2 wherein the rotatable shaft is provided with a crank structure and the strap assembly connects the crank structure to the forward end of the elongated rod.

4. A vacuum cleaner as claimed in claim 2 wherein the elongated rod is provided with threaded ends, a nut secured to a part of the strap assembly through which an adjacent threaded end of the rod is screw connected, the other threaded end of the rod being capable of being turned whereby the screw-connected end moves the strap assembly to thereby rotate the rotatable shaft and consequently adjust the position of the agitator relative to the surface to be cleaned.

5. A vacuum cleaner as claimed in claim 4 further comprising a parking lifter member having means coacting with the other threaded end of the rod whereby in one position of the parking lifter member with the vacuum cleaner housing in a vertical parking position the agitator is elevated to a position out of engagement with the surface to be cleaned.

6. A vacuum cleaner as claimed in claim 4 further comprising a parking lifter member having means coacting with the other threaded end of the rod whereby in one position of the parking lifter member with the vacuum cleaner housing in a position lowered from the vertical parking position the agitator is lowered to a position where it is in engagement with the surface to be cleaned.

7. A vacuum cleaner as claimed in claim 4 wherein the strap assembly is constituted of complementary upper and lower plates, an upstanding flange on each plate each provided with aligned openings, said nut fixed to one of said openings for receiving the adjacent a threaded end of the rod while the other opening is of bracket and the rod longitudinally. I 

1. A vacuum cleaner comprising: a. a hollow housing having an air inlet and an air discharge port, b. a dust collector, c. conduit means for conducting the air passing through the air inlet and depositing dust into the dust collector and thereafter passing the air out the air discharge port, d. an agitator for the surface to be cleaned being located in or adjacent to the air inlet, f. means for driving the agitator, f means mounting the agitator for substantially vertical movement including:
 1. a rotatable shaft mounted in said housing being operatively connected to the agitator,
 2. a resiliently biased member operatively connected to the rotatable shaft for moving the same to yieldably urge the agitator toward or away from the surface to be cleaned, g. an operator for moving the resiliently biased member, and h. said resiliently biased member including an elongated rod, a member mounted on said rod having an upstanding projection, said operator being provided with a surface that in one position thereof engages the upstanding projection in order to move the rod in a direction along the longitudinal axis thereof.
 2. A vacuum cleaner as claimed in claim 1 further comprising a strap assembly operatively connecting the forward end of the elongated rod to the rotatable shaft.
 2. a resiliently biased member operatively connected to the rotatable shaft for moving the same to yieldably urge the agitator toward or away from the surface to be cleaned, g. an operator for moving the resiliently biased member, and h. said resiliently biased member including an elongated rod, a member mounted on said rod having an upstanding projection, said operator being provided with a surface that in one position thereof engages the upstanding projection in order to move the rod in a direction along the longitudinal axis thereof.
 3. A vacuum cleaner as claimed in claim 2 wherein the rotatable shaft is provided with a crank structure and the strap assembly connects the crank structure to the forward end of the elongated rod.
 4. A vacuum cleaner as claimed in claim 2 wherein the elongated rod is provided with threaded ends, a nut secured to a part of the strap assembly through which an adjacent threaded end of the rod is screw connected, the other threaded end of the rod being capable of being turned whereby the screw-connected end moves the strap assembly to thereby rotate the rotatable shaft and consequently adjust the position of the agitator relative to the surface to be cleaned.
 5. A vacuum cleaner as claimed in claim 4 further comprising a parking lifter member having means co-acting with the other threaded end of the rod whereby in one position of the parking lifter member with the vacuum cleaner housing in a vertical parking position the agitator is elevated to a position out of engagement with the surface to be cleaned.
 6. A vacuum cleaner as claimed in claim 4 further comprising a parking lifter member having means co-acting with the other threaded end of the rod whereby in one position of the parking lifter member with the vacuum cleaner housing in a position lowered from the vertical parking position the agitator is lowered to a position where it is in engagement with the surface to be cleaned.
 7. A vacuum cleaner as claimed in claim 4 wherein the strap assembly is constituted of complementary upper and lower plates, an upstanding flange on each plate each provided with aligned openings, said nut fixed to one of said openings for receiving the adjacent threaded end of the rod while the other opening is of sufficient size to permit the rod to move freely therethrough.
 8. A vacuum cleaner as claimed in claim 1 wherein the member is a bracket that is mounted on the rod and upon the manipulation of the operator the eccentric surface engages the projection and thereby shifts the bracket and the rod longitudinally. 